New Android suppport
r/f? @mbrubeck
No need to r+ urgently; I want to do a little bit more testing of the release build, but I'm hoping to land this bit (moving to a more sane build process) next week.
The new version of building an APK:
1) Removes the glutin-based APK builder from the link step
2) Adds a build.rs step to the build of the final Servo library that adds the native code required by glutin's android_rs_glue (e.g., `ANativeActivity_onCreate` definition)
3) Replaces the link step with a `fake-ld.sh` script that instead creates a libservo.so
4) Adds a new mach `package` step to build the APK that has some Rust code that builds the library from a set of in-tree build files
This setup fixes a number of problems:
1) We can use gdb, because we use `ndk-build`, which adds the .gdbserver info, plus we keep around all of the build files (also required by the ndk gdb)
2) We can add more Java code & hooks to handle Android intents
3) We no longer have any git submodules or the awkward two-step build with android-rs-glue
Many other setups were tried (and failed). The most obvious ones is building a libservo.so from a `dylib` target from the servo build on Android. This doesn't work because you can't have a different default lib target on one platform than others in Cargo, and you also can't pass it in from the commandline (e.g., --lib does not have a dylib arg). Additionally, if you don't go through the intermediate libservo.rlib step (which removes unused symbols), then you end up with a TON of missing symbols because our -sys crates are super sloppy about that. I spent a few weeks beginning to clean them up, but since it's something we can't easily enforce (and new -sys packages will have this problem, too, since it's only an issue with the Android loader), it made more sense to me to just have the build set up to discard those unused bits of code before they ever get to the linker, much less the loader.
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Correct event dispatching for multiple simultaneous touch points
Instead of just converting the mouse into a single "touch" input, Servo can now listen for multi-touch events from Glutin, maintain a list of active touch points, and dispatch events for all of them.
r? @glennw (for the compositor changes) and @jdm (for the DOM changes)
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Make executing synthesized pinch zoom more similar to zoom
Synthesized pinch zoom was removed in #8121 so that this combination of
mouse wheel and key press can be handled by the page. I mistakenly
re-implemented it #8215. In order to preserve synthesized pinch zoom,
which is very useful for testing on desktop computers, have it work
similarly to page zoom except with the ALT key pressed.
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Add destructors to some WebGL objects, remove duplicated glutin dependency and try to enable the webgl reftests
The first commit allows to cleanup the gl resources of the webgl task earlier if they aren't being used.
Right now all resources were cleaned up when the context was destroyed, so I think this is
a slightly better approach.
The second commit bumps rust-offscreen-rendering-context to remove the duplicated glutin dependency.
The third one tries to reenable the webgl reftests.
Since the errored builds are deleted, It's the only way I can try to troubleshoot it.
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Before passing these layers to the paint task, expand them to pixel
boundaries. This ensures that subpixel edges of the layer will not be
clipped away and helps prevent rounding issues with layer contents.
Fixes#8166.
This uses the new `release_max_level` feature added in
rust-lang-nursery/log#58 to turn the `debug!` and `trace!` macros into no-ops
in optimized builds.
Synthesized pinch zoom was removed in #8121 so that this combination of
mouse wheel and key press can be handled by the page. I mistakenly
re-implemented it #8215. In order to preserve synthesized pinch zoom,
which is very useful for testing on desktop computers, have it work
similarly to page zoom except with the ALT key pressed.
The GLFW port had pinch zoom emulation that could be triggered by
holding control and using the mouse wheel. This was very useful for
testing pinch zoom behavior on desktop machines. This commit
implements this for the glutin port.
Instead of always promoting iframes to StackingContexts, integrate them
into the display list. This prevents stacking bugs when
non-stacking-context elements should be drawn on top of iframes.
To accomplish this, we add another step to ordering layer creation,
where LayeredItems in the DisplayList are added to layers described by
the LayerInfo structures collected at the end of the DisplayList.
Unlayered items that follow these layered items are added to
synthesized layers.
Another result of this change is that iframe layers can be positioned
directly at the location of the iframe fragment, eliminating the need
for the SubpageLayerInfo struct entirely.
Iframes are the first type of content treated this way, but this change
opens up the possibility to properly order canvas and all other layered
content that does not create a stacking context.
Fixes#7566.
Fixes#7796.
